Hey everyone, I'm excited to present this project to the community. I'm no stranger to car forums, and am excited to pick your collective brains as I get elbows-deep into this swap. Forum members have been such great help in my past projects. I like to tinker with my 1994 Mustang 5.0, and there were months where the forum rabbit-hole would just consume hour after hour of my life.
The idea here is to take the AAZ diesel out of my totalled 1995 VW Golf, and put it into a 2004 GMC Jimmy 4x4 I was given for free. Budget swap. The 4.3vortec in the Jimmy is blown, the car isn't running, but the transmission and tcase are fine and the body/interior/etc are in good condition.
The Golf situation is tragic really... I live in a snowy climate, and the neighbour's snow clearing contractor just massacred my 1995 Golf that was parked in MY driveway with his damn backhoe last week. I'll post some photos, he destroyed it. I loved that car... I loved the AAZ, I loved the 5-speed manual, I loved the 4-door and hatch, and I loved the size and simple-practical design of the car. I used the thing like a little pickup truck, plywood in the back, etc. Roof racks. Straight pipe. I also found it plenty quick for a daily driver, fun to drive even. Stock form. Brand new snow tires 2 seasons ago. Brand new headlight and side marker kits, smashed. Least to say, I'm pissed. Interior was mint. Underbody had rust, and it needed a rear-wheel-bearing. It did have over 300,000kms on it, but it didn't deserve to die like this.
Moving on. The Jimmy is my Aunt's. I'm pretty sure she got it new in 2004. 4-door, white on grey, switchable 4x4, power accessories, cloth seats, lift gate. Kind of like a larger, full-framed 4x4 Golf. It's had one accident, front fender hit turning left on a yellow years ago. Fixed no problem. Strangely enough, a few days after my beloved Golf got crushed like a beer can, my Aunt bought a brand new Ford Escape. She recently blew the engine in the Jimmy running it out of oil, decided to treat herself to something new instead of fixing the Jimmy. I offered to buy the salvage Jimmy, and once she heard about my Golf just decided to donate it for free.
So just conceptualizing this (and feel free to chime in), my initial thought is to take off the 5-speed manual and try to mate the AAZ flywheel to the Jimmy's stock torque converter. I'm not sure how the stall will work out, but the AAZ does rev more like a gasser than other diesels. I'm thinking it might just work out behind the 4-speed auto, mounted longitudinally. Fit shouldn't be a problem. I would think the ECU should still control the transmission the same with the engine removed. Anti-lock brakes, gauges, tcase switching, etc, should all be unaffected (I hope). I might need to rig up a tach signal off the alternator or something of the sort, I'll have to do more research. The Golf's fuel pickup could probably be adapted to the Jimmy's tank (unless there's an easier way) and I would yank the GMC fuel pump and run the stock AAZ lift pump. I would love a manual, but I think it would be a pain in the ass. Clutch, shifter, trans mounts, driveshaft, tcase (or delete 4x4... but 4x4 is awesome). I want this to be a simple, done-in-a-month kind of swap. I know I'm leaving torquiness, fuel economy, and power on the table by going with the stock auto. In the future, I may consider a manual swap if I do any kind of suspension or lift/tire combos. Maybe even a different torque converter on the stock auto would suffice to get it driving well. Anyone know if you can just... bolt/weld a flywheel from one engine onto a torque converter of another transmission?
Now practical matters. Will the AAZ have enough power for this Jimmy to run okay at highway speeds (100 km/h). Will it climb mountain passes okay when it kicks down into gear and starts revving up. My logic is that they seem to work in Westfalia camper vans, and Toyota pickup trucks, so why not the Jimmy? The fun part of this whole swap is I get to play with the engine after everything is running okay. I've always wanted to play with it in the Golf, and now with the heavier platform I'll need the power more than just a luxury. It would be cool to tow a trailer from time to time.
From the Cummins perspective, compound turbos and big-fuel P-Pumps are king. I would love to do something similar with the AAZ. Keep the stock turbo since it lights up so quick, and compound it with a larger turbo and heavy fuelling in the high RPMS and at full-fuel. What I visualize is the AAZ should drive exactly as it does now when you don't mash the pedal. No smoke, good light throttle manners, stock-level power. Just pushing torque through the drivetrain, nothing crazy, nice and efficient, the stock turbo might light up on the odd hill and during brisker accelerations to keep the push on. Then, I want to be able to just MASH that pedal at ANY RPM and dump a ton of fuel. Big cloud of smoke for a second until the second turbo lights up, then full-boost full-fuel until redline. Kind of like a bi-polar engine. Anyone seen those videos on youtube of the supposed 450+ HP TD MK3 Golf? Andy2turbo and tricksieboy are their accounts on youtube. I want that level of crazy, if possible... but only at full-fuel, to get the big turbo fired up. I wonder if Giles can build me such an animal of a pump. Being hooked to an auto might be beneficial too, to stay in boost without having to clutch-and-shift. Lock up the torque coverter, plow through the gears leaving a trail of smoke, both turbos screaming, full-weight Jimmy charging up a mountain grade like a freight train. But around town, meanders through the gears politely, no smoke, only lighting that little turbo. That's what I want to build. Again, feel free to chime in or give links to your setup if it sounds like what I'd be looking to try. I am a complete rookie when it comes to VW diesel performance, so I don't even know if it's possible to build the characteristics I'm looking for into a Bosch VE pump and a couple non-vnt regular turbos, but it seems like Andy2 had a good run. Streetability is my concern though. Moving on, I'm happy to run an intercooler and a small nitrous shot would be great if the internals would tolerate it. Even a modest 25hp dry shot post-intercooler on a steering-wheel-mounted pushbutton in series with a WOT switch to kick-up the torque and clear some unburned fuel on demand would be pretty cool. Please chime in
EGT gauge would be standard issue. I'm also not too concerned about fuel economy because I know it will be respectable compared to the truck in stock form (if you don't hit the fuel pedal too much). 30 mpg on the highway in overdrive would be cool. Guess it depends where the revs sit at cruising. My AAZ in the Golf got an average of ~37 mpg mixed driving over the 3-4ish years I've had the car. I tracked every tank. Will do the same with the Jimmy.
Anyways, thanks for reading. The goal is to take the heart and spirit of my beloved Golf, and give my Aunt's Jimmy another lease on life, on a budget, and planning to make it as powerful as reliability will allow. It will be my daily driver, run-around-town and road trips for skiing. Winter vehicle to replace the Golf, and I switch to the '94 Mustang for the summer months. I'm 28, and in a few years it could become a family vehicle. But... also has a pair of balls, because everything that I own that moves under it's own power needs to be respectable. The project start date is April 1st, and hoping to be buttoned up by early May. Keep an eye on this thread
